[light_hue_1]

There are no RNA-based lifeforms. All known life is DNA based but uses RNA internally. The earliest common ancestor of all life was DNA based, LUCA https://en.wikipedia.org/wiki/Last_universal_common_ancestor

There is a hypothesis that once upon a time life passed though an RNA only stage without DNA and proteins. RNA world https://en.wikipedia.org/wiki/RNA_world

[ababaian]

I like to view it that we're all RNA-based lifeforms. Operationally: DNA, RNA, or other are just a vehicles which hold our information.

This podcast RadioLab with Carl Zimmer (11m) I think captures the essence of the idea near perfectly: https://radiolab.org/podcast/creation-translation

[lolinder]

The premise of TFA is that we're treating viruses and virus-like things as a class of lifeform. There are RNA viruses, and these obelisk things are also RNA-based. Presumably that's what OP is asking about with regard to RNA-based lifeforms.

[cyberax]

> There are no RNA-based lifeforms.

There are viruses that have entirely RNA-based lifecycle (even using RNA-dependent RNA polymerase). Our very favorite COVID virus is one of them.